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authorValentin Popov <valentin@popov.link>2024-01-08 00:21:28 +0300
committerValentin Popov <valentin@popov.link>2024-01-08 00:21:28 +0300
commit1b6a04ca5504955c571d1c97504fb45ea0befee4 (patch)
tree7579f518b23313e8a9748a88ab6173d5e030b227 /vendor/exr/examples/7_write_raw_blocks.rs
parent5ecd8cf2cba827454317368b68571df0d13d7842 (diff)
downloadfparkan-1b6a04ca5504955c571d1c97504fb45ea0befee4.tar.xz
fparkan-1b6a04ca5504955c571d1c97504fb45ea0befee4.zip
Initial vendor packages
Signed-off-by: Valentin Popov <valentin@popov.link>
Diffstat (limited to 'vendor/exr/examples/7_write_raw_blocks.rs')
-rw-r--r--vendor/exr/examples/7_write_raw_blocks.rs115
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diff --git a/vendor/exr/examples/7_write_raw_blocks.rs b/vendor/exr/examples/7_write_raw_blocks.rs
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+
+#[macro_use]
+extern crate smallvec;
+extern crate rand;
+extern crate half;
+
+use std::convert::TryInto;
+use std::io::BufWriter;
+use std::fs::File;
+use exr::block::{UncompressedBlock};
+use exr::block::writer::ChunksWriter;
+
+// exr imports
+extern crate exr;
+
+/// Generate a striped image on the fly and directly write that to a file without allocating the whole image at once.
+/// On my machine, this program produces a 3GB file while only ever allocating 4MB memory (takes a while though).
+fn main() {
+ use exr::prelude::*;
+ use attribute::*;
+ use exr::math::*;
+
+ // pre-compute a list of random values
+ let random_values: Vec<f32> = (0..64)
+ .map(|_| rand::random::<f32>())
+ .collect();
+
+ // resulting resolution (268 megapixels for 3GB files)
+ let size = (2048*8, 2048*8);
+
+ // define meta data header that will be written
+ let header = exr::meta::header::Header::new(
+ "test-image".try_into().unwrap(),
+ size,
+ smallvec![
+ attribute::ChannelDescription::new("B", SampleType::F32, true),
+ attribute::ChannelDescription::new("G", SampleType::F32, true),
+ attribute::ChannelDescription::new("R", SampleType::F32, true),
+ attribute::ChannelDescription::new("Z", SampleType::F32, true),
+ ],
+ );
+
+ // define encoding that will be written
+ let mut header = header.with_encoding(
+ Compression::Uncompressed,
+
+ exr::meta::BlockDescription::Tiles(TileDescription {
+ tile_size: Vec2(64, 64),
+ level_mode: LevelMode::Singular,
+ rounding_mode: RoundingMode::Down
+ }),
+
+ LineOrder::Increasing
+ );
+
+ // add some random meta data
+ header.own_attributes.exposure = Some(1.0);
+
+
+ let headers = smallvec![ header ];
+
+ // specify output path, and buffer it for better performance
+ let file = BufWriter::new(File::create("3GB.exr").unwrap());
+
+ let start_time = ::std::time::Instant::now();
+
+ // finally write the image
+ exr::block::write(
+ file, headers, true,
+ |meta_data, chunk_writer|{
+
+
+ let blocks = meta_data.collect_ordered_blocks(|block_index|{
+ let channel_description = &meta_data.headers[block_index.layer].channels;
+
+ // fill the image file contents with one of the precomputed random values,
+ // picking a different one per channel
+ UncompressedBlock::from_lines(channel_description, block_index, |line_mut|{
+ // TODO iterate mut instead??
+
+ let chan = line_mut.location.channel;
+
+ if chan == 3 { // write time as depth (could also check for _meta.channels[chan].name == "Z")
+ line_mut.write_samples(|_| start_time.elapsed().as_secs_f32())
+ .expect("write to line bug");
+ }
+
+ else { // write rgba color
+ line_mut
+ .write_samples(|sample_index| random_values[(sample_index + chan) % random_values.len()])
+ .expect("write to line bug");
+ }
+ })
+ });
+
+ // print progress only if it advances more than 1%
+ let mut current_progress_percentage = 0;
+
+ chunk_writer
+ .on_progress(|progress|{
+ let new_progress = (progress * 100.0) as usize;
+ if new_progress != current_progress_percentage {
+ current_progress_percentage = new_progress;
+ println!("progress: {}%", current_progress_percentage)
+ }
+ })
+ .compress_all_blocks_parallel(&meta_data, blocks)?;
+
+ Ok(())
+ }
+ ).unwrap();
+
+ // warning: highly unscientific benchmarks ahead!
+ println!("\ncreated file 3GB.exr in {:?}s", start_time.elapsed().as_secs_f32());
+}